• Title/Summary/Keyword: Toll-Like Receptors

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Differential Expression of Th1- and Th2- Type Cytokines in Peripheral Blood Mononuclear Cells of Murrah Buffalo (Bubalus Bubalis) on TLR2 Induction by B. Subtilis Peptidoglycan

  • Shah, Syed M.;Ravi Kumar, G.V.P.P.S.;Brah, G.S.;Santra, Lakshman;Pawar, Hitesh
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.7
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    • pp.1021-1028
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    • 2012
  • Peripheral blood mononuclear cells (PBMCs) discriminate microbial pathogens and induce T-cell responses of appropriate effector phenotype accordingly. Toll-like receptors (TLRs), in part, mediate this microbial recognition and differentiation while the development of T-cell effector functions critically depends on the release of Th1- or Th2- type cytokines. In the present study, buffalo PBMCs were stimulated under in vitro culture conditions by Bacillus subtilis cell wall petidoglycan, a TLR2 ligand, in a dose- and time- dependent manner. The expression of TLR2 as well as the subsequent differential induction of the Th1 and Th2 type cytokines was measured. Stimulation was analyzed across five doses of peptidoglycan ($10{\mu}g/ml$, $20{\mu}g/ml$, $30{\mu}g/ml$, $40{\mu}g/ml$ and $50{\mu}g/ml$) for 3 h, 12 h, 24 h and 36 h incubation periods. We observed the induction of TLR2 expression in a dose- and time-dependent manner and the peptidoglycan induced tolerance beyond $30{\mu}g/ml$ dose at all incubation periods. The correlation between peptidoglycan stimulation and TLR2 induction was found positive at all doses and for all incubation periods. Increased production of all the cytokines was observed at low doses for 3 h incubation, but the expression of IL-4 was relatively higher than IL-12 at the higher antigen doses, indicating tailoring towards Th2 response. At 12 h incubation, there was a pronounced decrease in IL-4 and IL-10 expression relative to IL-12 in a dose- dependent manner, indicating skewing to Th1 polarization. The expression of IL-12 was highest for all doses across all the incubation intervals at 24 h incubation, indicating Th1 polarization. The relative expression of TNF-${\alpha}$ and IFN-${\gamma}$ was also higher while that of IL-4 and IL-10 showed a decrease. For 36 h incubation, at low doses, relative increase in the expression of IL-4 and IL-10 was observed which decreased at higher doses, as did the expression of all other cytokines. The exhaustion of cytokine production at 36 h indicated that PBMCs became refractory to further stimulation. It can be concluded from this study that the cytokine response to sPGN initially was of Th2 type which skews, more pronouncedly, to Th1 type with time till the cells become refractory to further stimulation.

Effect of Vitamin E Supplementation on Intestinal Barrier Function in Rats Exposed to High Altitude Hypoxia Environment

  • Xu, Chunlan;Sun, Rui;Qiao, Xiangjin;Xu, Cuicui;Shang, Xiaoya;Niu, Weining;Chao, Yu
    • The Korean Journal of Physiology and Pharmacology
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    • v.18 no.4
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    • pp.313-320
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    • 2014
  • The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia + vitamin E (250 mg/kg $BW^*d$) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma ($IFN-{\gamma}$) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and $I{\kappa}B{\alpha}$, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha ($HIF-1{\alpha}$ and $HIF-2{\alpha}$), Toll-like receptors (TLR4), P-$I{\kappa}B{\alpha}$ and nuclear factor-${\kappa}B$ p65(NF-${\kappa}B$ P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-${\kappa}B$ signaling pathway.

Anti-acne Properties of Artemisia annua Extract In Vitro (개똥쑥 추출물의 항여드름 효능확인)

  • You, Jiyoung;Roh, Kyung-Baeg;Oh, Se-young;Jung, Yong-Taek;Park, Deokhoon;Jung, Eunsun
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.3
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    • pp.247-254
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    • 2021
  • Acne vulgaris is a chronic inflammatory skin disease related to pilosebaceous unit. In acne lesions, hyperseborrhea, dysseborrhea, inflammatory event, and an imbalance in skin microflora, particularly an increase in Cutibacterium acnes (C. acnes) colonization comparing to other bacteria, have been observed. The objective of this study was to evaluate anti-acne effects of Artemisia annua extract (AAE) on antibacterial activity related to preservation of the balance in skin microbiome, inhibition of inflammation, and reduction of excessive sebum production. When C. acnes and Staphylococcus epidermidis (S. epidermidis) were co-cultured in the presence of AAE, the reduction of C. acnes growth by AAE was greater than that of S. epidermidis. In addition, when C. acnes was cultured in a medium containing AAE (C. acnes AAE), levels of cytokines such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and IL-6 and toll-like receptors-2 activity were decreased in comparison with C. acnes cultured in a medium without AAE (C. acnes CM). Moreover, AAE significantly inhibited excessive sebum production induced by palmitic acid. These results suggest that AAE, as a natural extract with various targets, can inhibit selective growth of C. acnes and inflammatory reactions derived from C. acnes, which are the main causes of acne, and consequently can be used as a substance to alleviate acne by reducing excessive sebum formation.